Secondary Battery Activation with Alternating Current SEI Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The aging process for secondary batteries is time-consuming, necessitating a method to stabilize the Solid Electrolyte Interface (SEI) film in a shorter duration to enhance productivity and maintain battery performance.
Innovation Solution
A method involving primary charging followed by alternately applying + and - currents at the end of the charging process, combined with room temperature and high temperature aging steps, to stabilize the SEI film efficiently, reducing overall activation time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional primary charging process is used to form the SEI film, then the battery structure is stabilized, but the aging time becomes excessively long
Solution Approach 1:
The patent applies periodic charging and discharging cycles at the end of primary charging, where + and - currents are alternately applied to the battery. This periodic action promotes uniform lithium ion distribution and accelerates SEI film stabilization, reducing the required aging time from conventional extended periods to just 3-24 hours while maintaining reliable battery structure
Solution Approach 2:
The patent changes the electrical parameters by applying alternating + and - currents with specific capacity ratios (0.1-2.0 C charging rate, 3-10% capacity change per cycle) after primary charging. These parameter changes create optimal conditions for rapid SEI film formation and stabilization, achieving the same reliability effect as conventional methods but with significantly reduced aging time
2Reliability
If the aging time is extended to ensure proper SEI film formation, then battery performance is maintained, but productivity decreases
Solution Approach 1:
By implementing periodic charge-discharge cycles with alternating currents during the final stage of primary charging, the patent accelerates the SEI film formation process. This reduces the required aging time from conventional extended periods to 3-24 hours, thereby maintaining battery performance while significantly improving production efficiency and productivity
Solution Approach 2:
The patent performs preliminary charge-discharge cycling at the end of primary charging before the aging process begins. This preliminary action pre-stabilizes the lithium ion distribution and initiates SEI film formation, so that the subsequent aging process requires much less time (3-24 hours) to complete, thus maintaining performance while enhancing productivity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach stabilizes the SEI film rapidly, shortening the aging time and maintaining battery performance equivalent to conventional methods, thereby increasing productivity and capacity retention.
Implementation Method 1
a primary charging step of charging a secondary battery including a positive electrode, a negative electrode, a separator and an electrolyte; a room temperature aging step of storing a secondary battery having gone through the primary charging step at a room temperature; and a high temperature aging step of storing the secondary battery having gone through the room temperature aging step at a high temperature, wherein at the end of the primary charging step, charging and discharging are performed by alternately applying + current and - current to the battery
Data Source
AI summary
The present invention relates to a method for activating a secondary battery. The present invention comprises: a primary charging step of charging a secondary battery including a positive electrode, a negative electrode, a separator, and an electrolyte; a room temperature-aging step of storing, at a room temperature, the secondary battery that has undergone the primary charging step; and a high temperature-aging step of storing, at a high temperature, the secondary battery that has undergone the room temperature-aging step, wherein charging/discharging is performed by alternately applying + current and − current to the secondary battery at the end of the primary charging step. The method for activating a secondary battery according to the present invention includes alternately applying + current and − current to the secondary battery at the end of the primary charging step to stabilize an SEI film, thereby shortening a following-up aging time.